Test Category: Immunology
Investigation Name:Complement Alternative Pathway AP50
Alias or Abbreviation:AP50, Functional complement
Intro:
Indication: Recurrent infections with encapsulated bacteria e.g. Neisseria meningitidis.Further information:
AP50 is a functional measure of alternative complement pathway activity. The Alternative complement pathway is an enzyme cascade dependent on stabilisation of C3b on microbial membranes.
Low AP50 values may be caused by complement consumption or deficiency of complement components or regulatory factors. Deficiencies of membrane attack complex components would lead to absent AP50 and CH50 results, whereas Factor B, D and properdin deficiencies would show normal CH50 values in the absence of AP50 activity.
Suspected complement deficiency should be investigated in anyone with recurrent infections with encapsulated bacteria
Pathology Laboratory:Immunology Laboratory
Requestable Seperately?Yes
Minimum Sample Volume:2mL
Expected Turnaround Time:28 working days
Test Code:A100
Sample Type:
Serum Gel Tube (Gold top)Complex Reference Range:Normal = >75 %
Abnormal = <75 %
Collection Conditions / Other Information:Urgent transport - Must be received in the laboratory within 1 hour of collection
Reference Laboratory Details:Immunology, Heartlands Hospital
Referred to Another Laboratory?Yes
Storage Requirements:Ambient temperature
Further information:Laboratory use only: Must be received in the laboratory and stored at < -70°C within 1 hour of collection. Must be sent to the referral laboratory to arrive frozen.
Lead Contact Details:Clinical Queries Email: rwh-tr.bcpsimmunologyclinicalqueries@nhs.net
Email Address For Chasing Results:rwh-tr.ImmunologyLab@nhs.net
Contact Number:01902695279
